BACKGROUND: Ovine anaplasmosis and theileriosis are important tick-borne diseases of sheep and goats which are distributed in the tropical and subtropical areas of the world. OBJECTIVES: This study was performed to assess hematological status in sheep naturally infected with Anaplasma and Theileria spp. to clarify the pathogenic aspects of various species involved in ovine anaplasmosis and theileriosis in Ahvaz region. METHODS: 109 sheep were sampled, and blood parasite infections were diagnosed by microscopic examination and PCR. The blood samples were also subjected to hematologic assessment. RESULTS: PCR analysis revealed A. ovis infection in 86.2% of sheep, while mixed infections with A. marginale were also detected in 53.2% of them. However, Anaplasma inclusion bodies were only observed in 32.1% of the tested animals. T. ovis were found in 88% of the inspected sheep by PCR, and 67.8% of them were detected microscopically, as well. Hematologic assessment showed that mean RBC, PCV, Hb, and MCHC were significantly lower, whereas MCV and RDW were higher in the animals with mixed infections of Anaplasma with parasitemia and Theileria, compared to the uninfected sheep and groups with single infection or without parasitemia. CONCLUSIONS: In brief, it seems that Anaplasma can be activated and induce its pathogenesis in the presence of other infective agents in the carrier or asympthomatic animals. It can also be concluded that mixed infections of Anaplasma with parasitemia and Theileria may induce a regenerative anemia which is most likely attributable to a combined effect of the two.

BACKGROUND: Anaplasmosis is caused by an obligate intracellular, gram-negative microorganism, which be-longs to the family Anaplasmatacea and can be transmitted by ticks and other arthropods. OBJECTIVES: The present study aimed to investigate the status of Anaplasma spp. infection by microscopy and molecular methods in dromedary camels in Bushehr province, Iran. METHODS: A total of 139 blood samples were collected from dromedary camels in Bushehr province. Giemsa staining and nested-polymerase chain reaction (PCR) were conducted to detect Anaplasma infection in the drome-dary camels. RESULTS: We found that 27 (19.4%) out of the total 139 blood samples were suspected for the presence of Ana-plasma spp. by morphological study. The PCR and nested-PCR sequencing results showed 111 (80%) and 134 (96%) samples positive for Anaplasma spp. and BLAST search in NCBI GenBank presented 100% identity with Candidatus Anaplasma camelii. CONCLUSIONS: The molecular results presented the high frequency of Candidatus Anaplasma camelii in camels, in Bushehr city.